Heat center Chris Bosh soars in for a dunk during Game 4 of the NBA Finals vs. Tim Duncan and the Spurs. / Derick E. Hingle, USA TODAY Sports

by Jeff Zillgitt, USA TODAY Sports

by Jeff Zillgitt, USA TODAY Sports

SAN ANTONIO - Chris Bosh apologized to his teammates for his performance against the Indiana Pacers in the Eastern Conference finals.

He gave the Miami Heat an F for their Game 3 loss against the San Antonio Spurs in the NBA Finals. He has been the subject of ridicule and scorn for the way he has played in the playoffs, specifically against Pacers big men Roy Hibbert and David West and Spurs center Tim Duncan.

This postseason has not featured Bosh's best basketball.

But in Game 4 against the Spurs on Thursday, the Heat center turned in his finest moment: 20 points, 13 rebounds, two blocks and two steals and a defensive effort that prevented San Antonio from dominating the paint and collecting crucial offensive rebounds.

"I want to play well every game," Bosh said. "I want to play to the best of my ability, and sometimes that doesn't happen. You're going to have bad games in a long stretch, especially during the playoffs. And that's when you kind of really have to trust your game and trust what got you here.

"Before I was really just trying to force some situations, thinking of how I can really get going and it doesn't work like that. I just have to really trust my instincts, trust my teammates and just continue to play and let things happen."

Bosh is a lightning rod for criticism. When he finishes with seven points and three rebounds (Game 4 vs. the Pacers) or goes 6-for-16 (Game 1 vs. the Spurs), the critics bash.

Too soft offensively and defensively. Too many three-pointers. Not enough rebounds. Outsiders struggle to understand why Bosh plays the way he does. Heat coach Erik Spoelstra explained it on Friday, a day off for the players.

"it takes somebody that's probably capable of being a lightning rod for a lot of judgment, and unfairly also, because for this to work, we had to put him in situations that are out of the box and would open the door for easy criticism from the outside," Spoelstra said. "Everybody wants to put him in a conventional box of being a back-end center and provide that type of post game for us. But in reality he has to do so many other versatile things for us to make this thing work.

"So he has the mentality to be able to handle that and he has to wear a lot of different hats for us to be successful."

With the series tied at 2-2, Game 5 is Sunday (8 p.m. ET, ABC), and Miami will need another strong performance from Bosh if it wants to head back to Miami up 3-2.

After shooting a career-high 53.5% from the field during the regular season, Bosh has slipped to 46.2% in the postseason, including 37.7% against the Pacers. His rebounding, at times, has been wretched - 4.3 per game against Indiana.

But Bosh has double-doubles in his past three games, with the Heat winning two. He also has attempted just one three-pointer since his 0-for-4 performance in Game 1. In those three games, he is averaging 14.7 points, 11 rebounds, two steals and two blocks and shooting 52.9% from the field.

"I don't know really what the difference has been with Chris. All we know is we need it," Spoelstra said. "And last night he played all his minutes at the center, where we needed it even more. It will be a collective effort. But there won't be anybody else we can turn to."

Spoelstra often says Bosh is the Heat's most important player. Not the best. Not the most valuable. But the most important. Miami's offense often runs through Bosh above the foul line, which is his comfort zone. From there, he can shoot, pass or drive. His presence away from the basket opens lanes for LeBron James and Dwyane Wade. That was in action in Game 4.

Defensively, Bosh patrols the back line at the rim and often gives up size and strength advantages to opposing big men, such as Hibbert and Duncan. He was outstanding Thursday.

"He was active," Shane Battier said. "When he's active, especially under the rim, it elevates our team to a higher level - just going up grabbing tough rebounds, which we had not been able to do in this series. When he plays like that, I like our chances."

Bosh is often thoughtful, entertaining and patient when answering questions. But he's also esoteric and honest with answers, doesn't always descend into clichés and sometimes has an edge.

After the Heat gave up 19 offensive rebounds in Game 3, Bosh had a simple answer to the problem: "Go get the damn ball," he said.

Wade and Bosh are neighbors, and Wade recently spent time at Bosh's house. Bosh played video games, and Wade talked.

"Chris is not a loose guy," Wade said. "He's quiet and to himself. The biggest thing was just trying to let him know how important he is, how important he was going to be to us winning this game tonight. He responded in a good way, but we got to continue to respond if we want to do what we did last year, and that's win a championship."

Bosh understands he has been asked to play an unconventional role for a big man and understands the pressure he is under to play well. Instead of resting easy after Game 4, Bosh wants to retain the feeling the Heat had after their Game 3 debacle.

"Whatever place that we were in after we got smashed on our Game 3, we need to stay there. We need to know what got us this win tonight. And we need to keep it. We need to think about it. And we need to continue to talk about it so we can keep that edge and bring the necessary energy for Sunday."